#include <stdio.h>
#include <unistd.h>
#include <sys/types.h>
int g_val = 100;

int main()
{
    printf("g_val: %d, &g_val: %p\n", g_val, &g_val);

    pid_t id = fork();
    if(id == 0)
    {
        while(1)
        {
            printf("我是子进程, pid: %d, ppid: %d, g_val: %d, &g_val: %p\n", getpid(), getppid(), g_val, &g_val);
            sleep(1);
            g_val++;
        }
    }
    else
    {
        while(1)
        {
            printf("我是父进程, pid: %d, ppid: %d, g_val: %d, &g_val: %p\n", getpid(), getppid(), g_val, &g_val);
            sleep(1);
        }
    }
	return 0;
}
